Both, the Federal Aviation Administration and the National Transportation Safety Board have sent experts to the scene.

The hot air balloon may have come into contact with power lines, Reuters quoted eyewitnesses as saying.

Caldwell County Judge Ken Schawe told CNN that the balloon could have collided with a power line, which could have triggered the fire and caused the crash. His theory is shared by a source from the Texas Department of Public Safety.

The pilot of the balloon was later identified as Skip Nichols, a chief pilot with Heart of Texas Hot Air Balloon Rides.

The worst-ever hot air balloon crash occurred in Luxor, Egypt in 2013. It resulted in the deaths of 19 of the 21 passengers on board, after the contraption caught fire when attempting to land. In 2012, a crash in Slovenia killed six people, when a balloon was blown towards the ground by a storm, and in New Zealand, 11 people died, after a tourist balloon became tangled in a power line. In both cases, the gas-powered aerostats were engulfed in rapidly-spreading flames.